1) It is possible that a maximally great being exists.2) If it is possible that a maximally great being exists, then a maximallygreat being exists in some possible world.3) If a maximally great being exists in some possible world, then amaximally great being exists in every possible world.4) If a maximally great being exists in every possible world, a maximallygreat being exists in the actual world.5) If a maximally great being exists in the actual world, then a maximallygreat being exists.6) Therefore maximally great being exists.

I've offered to explain why that's not a winner.

There are two ways to approach this. One can articulate the problems with each line, but that takes time. I'll do that, but let's start with the easy refutation. We'll use exactly the same reasoning to produce a contrary answer.

Any argument that provides contradictory answers is obviously wrong. It weighs nothing in the scales of persuasion. So,

1) It is possible that a maximally great being does not exist.2) If it is possible that a maximally great being doesn't exist, then a maximallygreat being doesn't exist in some possible world.3) If a maximally great being exists in some possible world, then amaximally great being exists in every possible world.

I'll stop for a moment to explain. We've already established that there are possible worlds where the MGB doesn't exist. So we get this:

P1: If the MGB doesn't exist in every possible world, then it doesn't exist in any possible world.P2: The MGB doesn't exist in every possible world.C: Therefore, the MGB doesn't exist in any possible world.

4) If a maximally great being doesn't exist in every possible world, a maximallygreat being doesn't exist in the actual world.5) If a maximally great being doesn't exist in the actual world, then a maximallygreat being doesn't exist.6) Therefore maximally great being doesn't exist.

I tried to add emphasis every time I made a change. Aside from step 1, my moves were all your moves. If they were legal for you, they were legal for me. My argument is exactly as strong as your argument, and yet the outcomes conflict.

This proves that the argument is bad. We'll go into why it is bad later, but at this point we understand that the ontological argument is worthless. The same logic "proves" both that god exists and that god doesn't exist. Worthless.

Okay, now it's time to look at this line by line, to see where exactly the flaws lie.

Here's the ontological argument as a whole:

1) It is possible that a maximally great being exists.2) If it is possible that a maximally great being exists, then a maximallygreat being exists in some possible world.3) If a maximally great being exists in some possible world, then amaximally great being exists in every possible world.4) If a maximally great being exists in every possible world, a maximallygreat being exists in the actual world.5) If a maximally great being exists in the actual world, then a maximallygreat being exists.6) Therefore maximally great being exists.

Okay, line one

1) It is possible that a maximally great being exists.

Kind of makes you wonder what a maximally great being is, doesn't it? Without knowing this, we can't say whether 1 is actually true.

2) If it is possible that a maximally great being exists, then a maximallygreat being exists in some possible world.

This bothers some people. But that's what "possible" means in possibleworldspeak, which is a fairly intuitive way of discussing otherwise difficult contralogical issues.

Some people are bothered by the very notion of possible worlds, but, again, it isn't some radical concept. We aren't saying that the worlds are really there. We're only using jargon to allegedly simplify certain discussions. Where one might say, "You might have knocked that over. If you had done so, it definitely would have broken," one might convey the same information by saying, "There are possible worlds in which you knocked that over, and in every one of those worlds, it broke."

The information is exactly the same. Only the jargon is different. There is no implication of mysterious worlds out there somewhere.

3) If a maximally great being exists in some possible world, then amaximally great being exists in every possible world.

Now I'm reading this as definitional. If you intend it otherwise, let me know.

What is an MGB (maximally great being)? We know absolutely nothing about it except this: It doesn't exist in any possible world unless it exists in all of them. This is the definition of MGB, and therefore it is true just because it is what we mean by the word.

Frankly I go back and forth on whether this definition is even coherent. Plantinga goes on about how to identify what is the same thing in two different worlds. The two most similar things are the same. But what about a possible world in which the thing most resembling me is an old bed spring? I'm a bed spring in that world? Or how about one world with many things and another with few? Things would have to map several-to-one; X in one would would have to be Y, Z, and Q in the other world.

That seems wrong to me. I'm not sure transworld identity even exists. But, when I say of something that you nearly knocked over, "In another world, you knocked that over," I'm clearly believing in at least some transworld identity.

So, I'm mentioning the transworld identity problem because it bothers me, but I'm not standing on it.

As far as I'm concerned, so long as 3 is intended as a definition of MGBs, I'm okay with it.

But now, now that we know something about MGBs, let's go back and look at 1.

1) It is possible that a maximally great being exists.

It's not true, is it? 1 is false.

We know that there are possible worlds without MGBs. We know that, because a possible world is, by definition, a world that doesn't have a logical contradiction. No square circles.

There is no logical contradiction involved in a world with no god. Plantinga admits this unambiguously in his free will argument.

Therefore,P1: MGBs don't exist in any possible world unless they exist in all of them. (Definition of MGB.)P2: Some possible worlds don't have MGBs.C: Therefore, MGBs do not exist in any possible world.

We know this. It follows from the definition. MGBs exist only in impossible worlds; they live with the square circles.

Note that the only reason we were confused about this is that Plantinga used slight-of-hand. He got us to agree that MGBs existed in some possible worlds before he told us what MGBs were. If he'd put step three before step one, he'd have fooled nobody, not even his most motivated believers.

At 10/24/2011 7:14:23 PM, JustCallMeTarzan wrote:Also, P3 is just stupid.

Then you don't understand S5 modal logic.

I took step 3 as definitional. If we read it as a statement of S5, which says something like, "anything that may exist must exist," then the ontological argument still fails.

I used to challenge S5 logic as stupid, but it seems to be orthodox, accepted. Presumably it has some use to some people in some circumstances, regardless of how contrarational it intuitively seems.

If we read step 3 not as a definition of maximally great beings, but rather as statement of S5 logic, then the ontological argument fails for my original reason: The same logic proves two conflicting things. If S5 turns a possibly-existent god into a definitely-existing god, then it also turns a possibly-not-existing god into a definitely-not-existing god.

Which puts us back to knowing that the ontological argument is worthless because any argument that proves both X and not-X to be true is worthless.

At 10/24/2011 7:14:23 PM, JustCallMeTarzan wrote:Also, P3 is just stupid.

Then you don't understand S5 modal logic.

I took step 3 as definitional. If we read it as a statement of S5, which says something like, "anything that may exist must exist," then the ontological argument still fails.

I used to challenge S5 logic as stupid, but it seems to be orthodox, accepted. Presumably it has some use to some people in some circumstances, regardless of how contrarational it intuitively seems.

If we read step 3 not as a definition of maximally great beings, but rather as statement of S5 logic, then the ontological argument fails for my original reason: The same logic proves two conflicting things. If S5 turns a possibly-existent god into a definitely-existing god, then it also turns a possibly-not-existing god into a definitely-not-existing god.

Which puts us back to knowing that the ontological argument is worthless because any argument that proves both X and not-X to be true is worthless.

The ontological argument weighs nothing on the scales of persuasion.

That's not what S5 is. According to S5, if something is possibly necessary, then it is necessary. That's not the same as saying that if it may exist, that it exists. Notationally, we can express it as:

<>[]P -> [] P

And that is not equivalent to

<>P -> []P

And in regards to the whole "possible non-existence of God objection," that just conflates epistemic possibility with metaphysical possibility. Metaphysically speaking, either God necessarily exists or he doesn't necessarily exist. So it comes down to whether or not you have more warrant for believing that his existence is possible over his existence being impossible. And surely it's more plausible to believe the former.

Aside from epistemic notions, Robert Maydole has also recently introduced a knockdown argument for the possibility premise in his modal perfection argument.

That's all I'm going to say. If anyone is interested, challenge me to a debate on the OA.

Official "High Priest of Secular Affairs and Transient Distributor of Sonic Apple Seeds relating to the Reptilian Division of Paperwork Immoliation" of The FREEDO Bureaucracy, a DDO branch of the Erisian Front, a subdivision of the Discordian Back, a Limb of the Illuminatian Cosmic Utensil Corp

At 10/24/2011 7:14:23 PM, JustCallMeTarzan wrote:Also, P3 is just stupid.

Then you don't understand S5 modal logic.

I took step 3 as definitional. If we read it as a statement of S5, which says something like, "anything that may exist must exist," then the ontological argument still fails.

I used to challenge S5 logic as stupid, but it seems to be orthodox, accepted. Presumably it has some use to some people in some circumstances, regardless of how contrarational it intuitively seems.

If we read step 3 not as a definition of maximally great beings, but rather as statement of S5 logic, then the ontological argument fails for my original reason: The same logic proves two conflicting things. If S5 turns a possibly-existent god into a definitely-existing god, then it also turns a possibly-not-existing god into a definitely-not-existing god.

Which puts us back to knowing that the ontological argument is worthless because any argument that proves both X and not-X to be true is worthless.

The ontological argument weighs nothing on the scales of persuasion.

That's not what S5 is. According to S5, if something is possibly necessary, then it is necessary. That's not the same as saying that if it may exist, that it exists. Notationally, we can express it as:

<>[]P -> [] P

Can you provide a reference? The closest axiom of S5 I can find is:

[]<>P -> <>P

And that is not equivalent to

<>P -> []P

And in regards to the whole "possible non-existence of God objection," that just conflates epistemic possibility with metaphysical possibility. Metaphysically speaking, either God necessarily exists or he doesn't necessarily exist. So it comes down to whether or not you have more warrant for believing that his existence is possible over his existence being impossible. And surely it's more plausible to believe the former.

Aside from epistemic notions, Robert Maydole has also recently introduced a knockdown argument for the possibility premise in his modal perfection argument.

That's all I'm going to say. If anyone is interested, challenge me to a debate on the OA.

At 10/24/2011 7:14:23 PM, JustCallMeTarzan wrote:Also, P3 is just stupid.

Then you don't understand S5 modal logic.

I took step 3 as definitional. If we read it as a statement of S5, which says something like, "anything that may exist must exist," then the ontological argument still fails.

I used to challenge S5 logic as stupid, but it seems to be orthodox, accepted. Presumably it has some use to some people in some circumstances, regardless of how contrarational it intuitively seems.

If we read step 3 not as a definition of maximally great beings, but rather as statement of S5 logic, then the ontological argument fails for my original reason: The same logic proves two conflicting things. If S5 turns a possibly-existent god into a definitely-existing god, then it also turns a possibly-not-existing god into a definitely-not-existing god.

Which puts us back to knowing that the ontological argument is worthless because any argument that proves both X and not-X to be true is worthless.

The ontological argument weighs nothing on the scales of persuasion.

That's not what S5 is. According to S5, if something is possibly necessary, then it is necessary. That's not the same as saying that if it may exist, that it exists. Notationally, we can express it as:

<>[]P -> [] P

Can you provide a reference? The closest axiom of S5 I can find is:

[]<>P -> <>P

And that is not equivalent to

<>P -> []P

And in regards to the whole "possible non-existence of God objection," that just conflates epistemic possibility with metaphysical possibility. Metaphysically speaking, either God necessarily exists or he doesn't necessarily exist. So it comes down to whether or not you have more warrant for believing that his existence is possible over his existence being impossible. And surely it's more plausible to believe the former.

Aside from epistemic notions, Robert Maydole has also recently introduced a knockdown argument for the possibility premise in his modal perfection argument.

That's all I'm going to say. If anyone is interested, challenge me to a debate on the OA.

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Official "High Priest of Secular Affairs and Transient Distributor of Sonic Apple Seeds relating to the Reptilian Division of Paperwork Immoliation" of The FREEDO Bureaucracy, a DDO branch of the Erisian Front, a subdivision of the Discordian Back, a Limb of the Illuminatian Cosmic Utensil Corp

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Only if the penis is maximally great.

That can't work here. The response to questioning the third premise of the argument was that JCMT didn't understand (translation: Didn't accept) S5 of modal logic. If this axiom of logic necessitates the 3rd premise of the OP, it necessitates it due to the structure of the argument, not the content "Maximally great being." Thus, if the argument is logical and no steps are left out, it is just as true for penises and humans as for maximally great beings and worlds.

It came to be at its height. It was commanded to command. It was a capital before its first stone was laid. It was a monument to the spirit of man.

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Only if the penis is maximally great.

That can't work here. The response to questioning the third premise of the argument was that JCMT didn't understand (translation: Didn't accept) S5 of modal logic. If this axiom of logic necessitates the 3rd premise of the OP, it necessitates it due to the structure of the argument, not the content "Maximally great being." Thus, if the argument is logical and no steps are left out, it is just as true for penises and humans as for maximally great beings and worlds.

No. That's just...wrong. The only way S5 works is if the thing being substituted into the equation is metaphysically necessary. A Maximally great being is metaphysically necessary - or to put it in s5 speak - A MGB is possibly necessary (exists in at least one possible world) and therefore exists in all possible worlds (from definition of metaphysically necessary) if it exists at all.

Official "High Priest of Secular Affairs and Transient Distributor of Sonic Apple Seeds relating to the Reptilian Division of Paperwork Immoliation" of The FREEDO Bureaucracy, a DDO branch of the Erisian Front, a subdivision of the Discordian Back, a Limb of the Illuminatian Cosmic Utensil Corp

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Only if the penis is maximally great.

That can't work here. The response to questioning the third premise of the argument was that JCMT didn't understand (translation: Didn't accept) S5 of modal logic. If this axiom of logic necessitates the 3rd premise of the OP, it necessitates it due to the structure of the argument, not the content "Maximally great being." Thus, if the argument is logical and no steps are left out, it is just as true for penises and humans as for maximally great beings and worlds.

No. That's just...wrong. The only way S5 works is if the thing being substituted into the equation is metaphysically necessary. A Maximally great being is metaphysically necessary - or to put it in s5 speak - A MGB is possibly necessary (exists in at least one possible world) and therefore exists in all possible worlds (from definition of metaphysically necessary) if it exists at all.

...so what Im taking away from this is that my MGP also exists in all possible worlds.

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Only if the penis is maximally great.

That can't work here. The response to questioning the third premise of the argument was that JCMT didn't understand (translation: Didn't accept) S5 of modal logic. If this axiom of logic necessitates the 3rd premise of the OP, it necessitates it due to the structure of the argument, not the content "Maximally great being." Thus, if the argument is logical and no steps are left out, it is just as true for penises and humans as for maximally great beings and worlds.

No. That's just...wrong. The only way S5 works is if the thing being substituted into the equation is metaphysically necessary.

Then there are missing steps from the argument.

Also, this calls into question the "logic" part of modal logic, as that's not a concern with the structure of the argument, as metaphysics, necessity, and metaphysical necessity are not found in the quoted argument.

(Of course, the whole notion of "possible worlds" doesn't make any sense).

A Maximally great being is metaphysically necessary - or to put it in s5 speak - A MGB is possibly necessary (exists in at least one possible world)

Those are two different statements. A penis exists on at least one possible human, that doesn't make it "possibly necessary" or your whole post is nonsensical.

It came to be at its height. It was commanded to command. It was a capital before its first stone was laid. It was a monument to the spirit of man.

All the ontological argument proves is that a necessary thing exists in all possible worlds. Circular logic, because the very definition of a necessary being is that it must exist in all possible worlds. The whole argument is glorified semantics.

It gets even more crazy when the OA is used to prove the existence of "god." God is defined by different religions in different way. The OA specifically defines god as a necessary being, then defines a necessary being as existing in all worlds if it exists in one possible world, assumes that it exists in one possible world, then deduces that it exists in all possible worlds. It simply goes around in circles proving nothing.

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Only if the penis is maximally great.

That can't work here. The response to questioning the third premise of the argument was that JCMT didn't understand (translation: Didn't accept) S5 of modal logic. If this axiom of logic necessitates the 3rd premise of the OP, it necessitates it due to the structure of the argument, not the content "Maximally great being." Thus, if the argument is logical and no steps are left out, it is just as true for penises and humans as for maximally great beings and worlds.

No. That's just...wrong. The only way S5 works is if the thing being substituted into the equation is metaphysically necessary.

Then there are missing steps from the argument.

No, it's you removing the argument from it's context. All those involved in serious debate about the argument are already familiar with modal logic and possible world semantics so it's not necessary to put a primer in about them every time the argument is laid out.

Also, this calls into question the "logic" part of modal logic, as that's not a concern :with the structure of the argument, as metaphysics, necessity, and metaphysical :necessity are not found in the quoted argument.

*sigh*

(Of course, the whole notion of "possible worlds" doesn't make any sense).

What?

A Maximally great being is metaphysically necessary - or to put it in s5 speak - A MGB is possibly necessary (exists in at least one possible world)

Those are two different statements. A penis exists on at least one possible human, that doesn't make it "possibly necessary" or your whole post is nonsensical.

What? A penis is a contingent thing. A penis is not possibly (metaphysically) necessary.

At 10/24/2011 9:41:16 PM, popculturepooka wrote:What? A penis is a contingent thing. A penis is not possibly (metaphysically) necessary.

Oh really? REALLY?

Official "High Priest of Secular Affairs and Transient Distributor of Sonic Apple Seeds relating to the Reptilian Division of Paperwork Immoliation" of The FREEDO Bureaucracy, a DDO branch of the Erisian Front, a subdivision of the Discordian Back, a Limb of the Illuminatian Cosmic Utensil Corp

At 10/24/2011 8:47:08 PM, Ragnar_Rahl wrote:If a penis exists on some possible human, it exists on every possible human!

I feel dirty.

Only if the penis is maximally great.

That can't work here. The response to questioning the third premise of the argument was that JCMT didn't understand (translation: Didn't accept) S5 of modal logic. If this axiom of logic necessitates the 3rd premise of the OP, it necessitates it due to the structure of the argument, not the content "Maximally great being." Thus, if the argument is logical and no steps are left out, it is just as true for penises and humans as for maximally great beings and worlds.

No. That's just...wrong. The only way S5 works is if the thing being substituted into the equation is metaphysically necessary.

Then there are missing steps from the argument.

No, it's you removing the argument from it's context.

It's a formalized argument with a list of numbered premises and conclusions. When you are doing that, you are announcing to the world "There is no context, no outside information necessary, the truth of the argument can be obviously seen from the logical structure."

All those involved in serious debate about the argument are already familiar with modal logic and possible world semantics

Logic doesn't care what you're "already familiar with" (let alone what you accept) If you can read the notation, you can understand the validity of a formal logical argument. Also, I'm reasonably convinced there that you're making a circular argument, as your definition of "engaging in serious debate about this" already likely contains a prior familiarity with and acceptance of modal logic and "possible worlds."

(Of course, the whole notion of "possible worlds" doesn't make any sense).

What?

When the only response one has is "What?" to that, it is acquiescence. As, after all, the notion that it DOES make any sense is the affirmative position. :P

A Maximally great being is metaphysically necessary - or to put it in s5 speak - A MGB is possibly necessary (exists in at least one possible world)

Those are two different statements. A penis exists on at least one possible human, that doesn't make it "possibly necessary" or your whole post is nonsensical.

What? A penis is a contingent thing.

Therefore "A penis exists on at least one possible human" does not establish its necessity. Therefore, "A maximally great being exists on at least one possible world" does not establish its necessity, leaving you with no argument to establish it as metaphysically necessary. If you merely assume it-- well, that's basically the conclusion, making the whole argument circular.

It came to be at its height. It was commanded to command. It was a capital before its first stone was laid. It was a monument to the spirit of man.